Table S1 - Explaining Global Increases in Water Use Efficiency: Why Have We Overestimated Responses to Rising Atmospheric CO2 in Natural Forest Ecosystems?

List of case studies that reported physiological changes in response to rising atmospheric CO2. (*) Indicates studies where annual percent change in iWUE was reported in the original text; (**) indicates studies where only δ13C series were presented. In all case studies iWUE was determined based on tree-ring δ13C following classic calculations (eq. 1 to 3) and using real values of atmospheric δ13C and CO2 concentrations [14], [15]. The equation that best describes the relationship between iWUE and CO2 series in each case study and the period of the observation are shown. From these relationships annual percent changes was calculated to project iWUE values over the past century (Fig. 3). (DOC)

本清单汇总了针对大气CO₂浓度升高引发生理变化的案例研究。带(*)标记的案例研究，其原文中报告了内在水分利用效率（intrinsic Water Use Efficiency, iWUE）的年变化率；带(**)标记的案例研究则仅提供了碳同位素比值δ¹³C序列。所有案例研究中的iWUE均基于树木年轮δ¹³C，通过经典计算公式（式1至式3）并结合大气δ¹³C与CO₂浓度的实测值[14,15]计算得到。各案例研究中用于描述iWUE与CO₂序列最优关系的方程式，以及观测时段均已列出。基于上述关系，研究人员计算了年变化率，以推演近一个世纪以来的iWUE数值（图3）。(DOC)